package com.sky.aspect;

import com.sky.annotation.AutoFill;
import com.sky.constant.AutoFillConstant;
import com.sky.context.BaseContext;
import com.sky.enumeration.OperationType;
import lombok.extern.slf4j.Slf4j;
import org.aspectj.lang.JoinPoint;
import org.aspectj.lang.annotation.Aspect;
import org.aspectj.lang.annotation.Before;
import org.aspectj.lang.annotation.Pointcut;
import org.springframework.stereotype.Component;
import org.aspectj.lang.reflect.MethodSignature;

import java.lang.reflect.Method;
import java.time.LocalDateTime;

//自定义切面，实现公共字段自动填充
@Aspect
@Component
@Slf4j
public class AutoFillAspect {

    //切点
    @Pointcut("execution(* com.sky.mapper.*.*(..)) && @annotation(com.sky.annotation.AutoFill)")
    public void autoFillPointCut()
    {

    }
    //前置通知
    @Before("autoFillPointCut()")
    public void autoFill(JoinPoint joinPoint)
    {
    log.info("自动填充公共字段");
    //获取被拦截方法上的数据库操作类型
        MethodSignature signature = (MethodSignature) joinPoint.getSignature(); //方法签名对象
        AutoFill autoFill   =  signature.getMethod().getAnnotation(AutoFill.class);//获取注解对象
        OperationType operationType = autoFill.value(); //获取数据库操作类型

    //获取被拦截方法上的实体类对象
        Object[] args = joinPoint.getArgs();
        if(args == null || args.length == 0){
            return;
        }
        Object entity = args[0];
        //为公共属性统一赋值（反射）
        LocalDateTime now = LocalDateTime.now();
        Long currentId = BaseContext.getCurrentId();
        if(OperationType.INSERT.equals(operationType)){
                //为四个字段赋值
            try {
                Method setCreateTime = entity.getClass().getDeclaredMethod(AutoFillConstant.SET_CREATE_TIME, LocalDateTime.class);
                Method setUpdateUser = entity.getClass().getDeclaredMethod(AutoFillConstant.SET_UPDATE_USER, Long.class);
                Method setUpdateTime = entity.getClass().getDeclaredMethod(AutoFillConstant.SET_UPDATE_TIME, LocalDateTime.class);
                Method setCreateUser = entity.getClass().getDeclaredMethod(AutoFillConstant.SET_CREATE_USER, Long.class);
                //通过反射为对象属性赋值
                setCreateTime.invoke(entity,now);
                setUpdateUser.invoke(entity,currentId);
                setUpdateTime.invoke(entity,now);
                setCreateUser.invoke(entity,currentId);
            } catch (Exception e) {
                throw new RuntimeException(e);
            }
        }else if(operationType .equals(OperationType.UPDATE)){
            //为两个字段赋值
            try {
                Method setUpdateUser = entity.getClass().getDeclaredMethod(AutoFillConstant.SET_UPDATE_USER, Long.class);
                Method setUpdateTime = entity.getClass().getDeclaredMethod(AutoFillConstant.SET_UPDATE_TIME, LocalDateTime.class);
                //通过反射为对象属性赋值
                setUpdateUser.invoke(entity,currentId);
                setUpdateTime.invoke(entity,now);
            } catch (Exception e) {
                throw new RuntimeException(e);
            }
        }
    }
}
